First Dinosaur Discovered in Spain Is Younger Than Believed

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The first dinosaur ever found in Spain is not as old as
paleontologists had believed — though at 130 million years old,
the long-necked creature is no spring chicken.

The dinosaur, Aragosaurus ischiaticus, was originally
discovered in 1987. But the
fossil was difficult to date. Now, researchers at the
University of Zaragoza's Aragon Research Institute of
Environmental Sciences have found the sauropod's age was
estimated at 15 million years too old. The age-shaving results
suggest the dinosaur was an ancestor of the enormous
Titanosauriforms, a group that includes the largest
dinosaurs to ever live.

The new age estimate puts the dinosaur in the Hauterivian age
between 136 million and 130 million years ago, the researchers
reported March 12 in the journal Geological Magazine.

"This is the only dinosaur of this period found in Spain and is
also the most intact in Europe," study author José Ignacio Canudo
of the University of Zaragoza said in a statement. "It can be
categorized amongst the well-known sauropods of the
Jurassic-Cretaceous transition (135 million years ago), the most
abundant species during the Barremian age (116 million years
ago). As this group has been studied the least,
the Aragosaurus fills the gap."

To accurately date the Aragosaurus specimen, Canudo and
his colleagues conducted fieldwork at the site of the find. They
used fossil pollen found in the same layers of sediment as the
Aragosaurus to pinpoint the date. By knowing the
evolutionary history and age
of the plants that released that pollen, the researchers can
estimate the ages of fossils found in the same layers.

The more accurate date helps flesh out the sauropod family tree,
the researchers reported. Aragosaurus fills a gap in
fossil knowledge during the shift from the Jurassic to the
Cretaceous period, Canudo said.